This study is testing the hypothesis that production of active vitamin D metabolites in human granuloma-forming disease like sarcoidosis is not subject to regulation by those physiological factors which normally control the renal synthesis of 1, 25 - (OH) 2D. Instead, it is thought that hormone production by macrophages in these disease states is regulated by locally produced or circulating immunomodulatory agents and in an intracrine/autocrine fashion by endogenously synthesized nitrous oxide and a vitamin D stimulatory factor. Bronchoalveolar lavage specimens are collected from patients undergoing bronchoscopy at both CSMC and USC.